This mods adds a couple new mechanics to vanilla Minecraft(Each one can be enabled or disabled by config):

Sword Blocking [1.8.x or below]: Blocking with a sword will reduce the battle damage you take by half, if sneaking, then the damage will be negated once. The sword will be damaged by the original amount of damage you would have taken. (Lore: Can't touch this)

Shield Parachuting: If falling, looking straight up or down while using a shield will slow the player's fall and reduce their fall damage - eventually reducing the damage to zero and allow the player to "float". The shield will be constantly damaged as the player continues to use this to cushion their fall.(Lore:*Internal screaming intensify*)

Arrow Throwing: Right clicking with an arrow in your hand will cause it to be throw. Its range is 5 blocks and deals 2 hearts of damage. (Lore: Take this arrow to the knee. TAKE IT)

Armor Swapping: Right clicking with an armor piece in hand will swap it with the respective armor piece you are currently wearing. (Lore: Do this armor make my skin look fat?)

Tools Block Placing: Like the Tinkers Construct tools, normal tools will be able to place blocks that is at the right or left of them in the hotbar. The tools will try to place the blocks to their right before trying to place the blocks on their left. If the tool is on the player's offhand, then it will try to place the blocks located to the right or left of the highlighted slot in their hotbox.

If sneaking, then the tool will mine and replace the block you are looking at with the block in the hotbar if it is the correct tool for the block-to-be-mined (The tool will get damaged). If the tool isn't the proper tool for that block, the block will in the hotbar will be placed on or by that block instead. (Lore: Look ma! No hands! Kinda.)

Sleeping: Sleeping will clear all potion effects (that can be clear by Milk) that you have and heal you by 20 hearts. Five hunger points will be reduced. There's a config where you can add more effects that sleeping will remove. (Lore: Nothing like a good night's rest)

Strength Effect Boost: Having a active Strength effect will allow you to shoot/throw arrows to a farther distance and deal extra damage. The more potent the effect is, the more farther the arrow goes. (Lore: Have some flying street justice!)

Weakness Effect Debuff: Having a active Weakness effect will lower the range in which your arrows will fly along with the damage. The more potent the effect is, the shorter the arrow will go. (Lore: My arm is so tired right now ;_;)

Jump Effect Step-Assist: Having a active Jump Boost effect will grant you the ability to walk up blocks as if you were wearing a Boot of the Traveler/Sojourners Sash. The more potent a effect is, the more blocks you can walk up - If you happens to be running. (Lore: Look ma! No spacebaring!... I'll leave now)

Ender Pearls: Using a Ender Pearl in the End will allow you to repeatedly without any cooldown. Creative mode players can use them anywhere without any cooldown restriction. (Lore: Tapping into the mysterious energy of the End, the pearls seems to have regain their lost powers. Allowing one to have unrestricted teleportation.)

Creative Eye Of Ender Teleport: Sneak right clicking with the Eye of Ender will teleport you to the nearest stronghold. Only happens if you are in creative mode.

Nether Block Burn: Breaking Netherrack or Quartz Ore will cause (non-source block) lava to spill out unless they are silk-touched or broken by hand. Additionally, but disabled by default, they will burn you if you are stepping on them while in the Nether (The burn time will depend on your difficulty, Easy = 1 seconds, Normal = 5 seconds, Hard = 10 seconds). (Lore: The red blocks from the Nether have interesting proprieties, breaking them within a range of frequency will cause them to spill out lava. Magic seems to negate the effect)

Soulsand Breakage: Breaking Soulsand will inflict the breaker with a slowness effect unless it was mined with silk-touch. The duration depends on your difficulty, Easy = 1 second, Normal = 5 second, Hard = 10 second. (Lore: These sands contains the souls of the tormented, breaking them cause its seal to become a bit undone and release some of the tormented souls. The chills as the soul pass your body freezes you in fear momentary. Magic seems to preserve the seal)

Player Collision: Player once again can bump against other entities, instead of just passing through them. This is disabled by default (Lore: Red Steve was pushed off a cliff by Blue Steve)

Inter-Dimensional Teleport command: This mod will provide a op-command that will can teleport you across dimension when MystCraft or RFTools are not present. The following is its usage (Note: the mod will calculate a safe height to place you in, but defaults to a height of 70 if it fails to do so. Best to be flying or in creative):

/tpd list - List the dimension ids, name, and the one you are currectly in
/tpd <Dimension Id> - Teleports you to that dimension
/tpd <Dimension Id> <x> <z>- Teleports you to that dimension at that x and z coordinate
/tpd <Dimension Id> <x> <y> <z>- Teleports you to that dimension at that x, y, and z coordinate
/tpd <Player Name> <Dimension Id> - Teleport that player to that dimension
/tpd <Player Name> <Dimension Id> <x> <z>- Teleport that player to that dimension at that x and z coordinate
/tpd <Player Name> <Dimension Id> <x> <y> <z>- Teleport that player to that dimension at that x, y, and z coordinate
/tpd <First Player Name> <Second Player Name> - Teleport the first player to the second player, regardless of their current dimension

For some reason the above crash is happening on our server if we have Survival Tweaks installed. The crash happens if any player is attacked, and causes the server to crash and have to be restarted with the above report.

I did not see anything about this only being for clients.

Edit: Forgot to mention, forge version is 1492, and this crash happens with both 1.0.0 and 1.0.1 versions of Survival Tweaks.

For some reason the above crash is happening on our server if we have Survival Tweaks installed. The crash happens if any player is attacked, and causes the server to crash and have to be restarted with the above report.

I did not see anything about this only being for clients.

Edit: Forgot to mention, forge version is 1492, and this crash happens with both 1.0.0 and 1.0.1 versions of Survival Tweaks.

I had accidentally included client-side only code in the last two versions. v1.0.2 should fix the problem, but I'm doing some extra testing on a private server before releasing it - just in case something slipped by me again.